Lock for sliding doors



United States Patent Oce Fatented Dec. 31, 1963 3,115,763 LUCK FR SLIDIGDOORS Allen R. Bartlett, Belmont, Calif., assigner to Mosier HarborMetal Products Corporation, Belmont, Calif., a corporation of CaliforniaFiled May 18, 1961, Ser. No. 110,934 3 Claims. (Cl. 70-100) Thisinvention relates to a lock which is adapted to secure or lock slidingdoors or panels against relative movement.

Conventional sliding doors are mounted in spaced parallel relationshipat the entrance to a cabinet, room, closet or the like, and aretranslationally movable in longitudinal dlrection along upper and/orlower tracks. The doors can be moved or slid relative to each otheralong their respective tracks between the opposite sides of the entrancearea, from closed position, in which the doors extend across the entireentrance area and overlap only along one edge, to open position, inwhich the doors substantially overlap each other. Such doors range insize from small cabinet doors to large doors several feet in height.

The present invention is directed to a lock for use with such doors, forsecuring them against relative longitudinal movement in a givendirection. This lock is further characterized in that it does not impedefree slidability of the doors past each other when it is in unlockposition, but in locking position it positively secures the doorsagainst transversely directed forces tending to spring them apart, aswell as against relative sliding movement.

Past lock constructions of the general type to which this inventionrelates have typically included a large and unsightly barrel which hasbeen necessary to provide the necessary throw, but which has usuallyprotruded outwardly from the face of the door, especially if the door isrelatively thin. Moreover, it has often been possible in the past togain access surreptitiously to the space behind the locked doors withoutoperating the lock, by springing the doors apart so that a gap ispresented between the marginal areas along which they overlap; the doorsare not damaged, particularly where they are large in surface dimension,and show no evidence of having been thus attacked.

The present lock overcomes these objections. It does not include alarge, objectionably protruding barrel, and is small enough to besuitable for use on small or thin doors, yet by means of a novelmechanism provides suficient throw to be equally suitable for use onlarge or thick doors. In unlock position, the lock elements do notproject substantially inwardly from the door on which the lock ismounted, and thus do not impede free sliding movement of the other doorof the pair. In lock position, however, the lock presents a bolt memberwhich extends perpendicularly inwardly from the door in position to abutor arrest sliding movement of the other door past it and, moreover,secures the doors against relative transverse movement, so that theycannot be sprung apart to gain entrance to the locked area.

Simply put, a preferred embodiment of my invention comprises akey-operated lock mechanism of the type wherein insertion and rotationof a key in a cylinder eects longitudinal movement of a cylinder-drivenbar or slider in a direction transverse or perpendicular to the axis ofrotation of the cylinder. A bolt member, which in lock position isadapted to engage the leading edge of a sliding door, is mounted at oneside of the lock mechanism for rotation about an axis which istransversely oriented with respect to the direction of movement of thebar. This bolt comprises a door-arresting arm portion having a ange atits outer end, and a cam portion connected to the arm portion forconverting transverse olf-axis force applied by the bar into rotation ofthe bolt about its axis in such manner that the arm is swung from anunlock position against the surface of the door to a lock position inwhich the arm extends inwardly from the door in line to arrest theleading edge of the other door. The ange at the tip of the arm isarranged so that in lock position it hooks or projects behind the otherdoor, thereby preventing the doors from being sprung apart.

One of the advantages of the lock I have invented is that the boltrotating or camming means may comprise a conventional key-operated lockmechanism of which the part referred to herein as the bar or slidercomprises the boit. This lock mechanism is combined with the bolt of thepresent invention in such manner that the bar is aligned in cammingrelation with the cam portion of the bolt. As the key is turned in thelock mechanism, rotational movement of the cylinder is converted intolinear movement of the bar, which is in turn converted by the camsurface into rotation of the bolt.

At the end of its travel the bar locks the cam against return movement,so that the arm is held in lock position. When the key is turned in theopposite direction to unlock the doors, the bar is drawn away from thecam shaft by the cylinder, and spring return means move the bolt arm toits original folded-away position against the door surface.

As will be apparent from the detailed description which follows, bycombining this key-operated actuating mechanism with the cam shaft andbolt arm, I have provided a lock having the necessary bolt throw yetwhich is small and does not protrude objectionably from the door, andwhich positively secures the doors against being sprung apart.

The invention can best be further described in relation to theaccompanying drawings, in which:

FIGURE 1 is a horizontal section through the overlapping marginalportions of two sliding doors in closed position, one of which is ttedwith a lock in accordance with a preferred embodiment of the presentinvention, showing the bolt in lock position;

FIGURE 2 is a rear elevation of the lock shown in FIG- URE 1illustrating the positions of the various elements in unlock position;

FIGURE 3 is horizontal section taken on line 3 3 of FIGURE 2;

FIGURE 4 is a rear elevation similar to FIGURE 2 but shows the lock inlock position, the bar driving means being partly broken away to showthe teeth formed in the bar; and

FIGURE 5 is a horizontal section taken on line 5-5 of FIGURE 4.

In FIGURE 1 -a pair of generally conventional sliding doors aredesignated 4by 10 and 11 respectively. While the construction of thedoors and 11 themselves is not a part of the invention, the doorsillustrated by way of example in the ydrawing are formed of sheet metal,and each comprise `a flat panel 12 having an inwardly turned edgeportion y1 3 and a ange 14 to rigidify the panels 12. The door 11 shownat the right in FIGURE l is mounted in the entrance area forwardly ofthe ydoor 10 shown to the left, the `doors being slidable along spacedparallel tracks (not shown) as is conventional.

The right door 11 is titte-d with a lock generally designated by 16which embodies the principles of my invention. Lock 16 includes asubstantially rectangular base plate 17 which may be made of metal, andwhich mounts the various elements of the lock -as described in detailhereinafter. No fittings are mounted to door |10.

The body 1S of a generally conventional key-'operated lock Imechanism`19 extends through openings 20 and Z1 in door panel 12 and base plate17 respectively (see FIG- URE 3) and is secured therein by a nut 22. Thetwo openings and 21 are preferably non-circular and are keyed to body 13so that the lock 16 `cannot rotate relative to the door. Lock mechanism19 is operated by a key 2,3 which is received in a cylinder or barrel 24extending through body 18. Cylinder 24- can be rotated in eitherclockwise or counterclockwise direction by turning key 23. The internalkey-receiving elements in body 18 may be conventional and yare notshown.

The inner end of cylinder 24 is provided with two spaced diametricallyaligned pins 26 and 27. The other ends of pins 26 and 27 Iare fastenedto a circular plate or disk 28 which is spaced from cylinder 24.Together, cylinder 24, pins 26 and 27 and disk 23 comprise a simplegear, as wi-ll be explained. As is best sho-wn in FIG- URES 3 and 5, aspacer 3d is preferably provided adja cent this gear, the surface ofspacer 30 being vgenerally co-planar with the surface of cylinder 24.This spacer is attached to body l by screws 31 or in other suitablemanner.

A bolt member .generally designated by 32 is mounted by base plate 17 tothe side of cylinder 24 for rotation about an axis which is vertical,i.e. which extends parallel tto the edges of doors lil and 1l. Bolt 32includes a cam shaft portion 33 and a door-engaging arm portion 34 whichis connected to cam shaft 33 by a reinforcing section 36. The surface ofcam shaft 33 is defined by a curved surface 37 and a substantially liatsurface 38 tangenial thereto. The arm portion 3dof bolt 32 extends a-tsubstantially right angles to the plane of fiat surface 38, as can bestbe seen in FIGURE 5.

At the outer end of arm 34 a flange at) is provided. The length of arm34, andthe position of ilange dit, is such that when the bolt 32 is inlock position, flange itl will project behind ange 14 of left door 10,and thereby positively prevent ithe doors from being sprung apart.

The cam shaft portion 33 of bolt 32 is provided with a longitudinal borethrough which an axle or pin 41 extends. The ends of axle 41 arereceived in concentrically bent tabs i2 of base plate 17. Torsion springmeans 43 are disposed around axle di, and one end of the spring abuts alinger 4d projecting from cam shaft portion 33. The other end of spring43 bears against the door panel 12, thereby urging the bolt 32 aboutaxle 41 toward unlock position.

From FIGURE 3 it can -be seen that an off-axis force directed `to theright against flat surface 3S of cam portion 33, of magnitude suicient'to overcome the force of spring 43, will rotate bolt 32 clockwise (asviewed in FIGURES 3 and 5) about axle 4l, whereby the door arresting arm34 will be moved from unlock position, tow-ard lock position.

The yforce for effecting such cam-med motion of arm 34 is provided inthe preferred embodiment of my invention by a member 46 which is drivenlongitudinally by the rotation of cylinder 24 and which may convenientlycomprise the bolt of the lock mechanism 19. rThis member 46 is agenerally rectangular bar having a 'cam engaging surface 47 at one endand a recessed slot 48 which extends toward surface 47. A series ofdrive teeth 56 are lformed in the web 51 defined by slot 48, as bestshown in FIGURE 4. Web 51 is disposed between cylinder 24 and disk 2S,the pins 26 and 217 co-acting with the teeth E@ of bar Se in rack andpinion relationship. The cam engaging surface of bar 46 is supported andguided in drive relationship with cam surface 3d by a U-shaped guide 52the legs of which are affixed to base plate 17, and by spacer 39, overwhich the inner surface of web 5l slides.

The operation of the lock may now be described. Assuming that the lockis in unlock position, as illustrated in FIGURES 2 and 3, insertion androtation of the proper key Z3 in lock mechanism 19 turns cylinder 24 andeffects linear' irnovement of bar i6 to the right, as the pins 26 and 27alternately engage the :teeth formed in bar 46 in rack and pinionrelation. The motion 4of bar 46 to the right is constrained by cylinder24 and disk 23 (between which vweb 51 is positioned), spacertl, andguide 52 so that the surface 47 of bar 46 engages cam surface 3S andturns the bolt clockwise about axle 41 against the counteracting torqueof spring 43. When arm 34 of a bolt 32 has been moved through an arc ofapproximately to the position `shown in FIGURE 5, surface 3S olf camportion 33 is substantially parallel to the direction of movement of bar46. Further longitudinal movement of bar 46 produces no additionalrotation of arm 3ft since the bar then overtravels, that is, it slidesover cam surface 38 and exerts no rotational force on it. However,movement of bar in beyond the position shown in FIGURE 5 to the positionindicated by the dotted lines in FIGURE l positively holds bolt 32Aagainst movement toward unlock position. Thus, in FGURE 1, it can beseen that relative movement of door liti to the right beyond the pointat which the leading edge 13 of door Iii abuts arm 34 is prevented sincebar i6 positively prevents rotation of the tcam `shaft 33 and arm 34.Force applied to arm 34 by attempting to force door 10 to the right istaken up by guide 52 to which such force is transmitted through camshaft 33 and bar 46.

In the embodiment shown in the drawings, the left and right ends of thetooth cutout 53 in bar t6 function as stops for limiting the degree towhich the bar can be moved by rotating key 23 and cylinder 24, rotationof the key through approximately 360 effecting full movement of the bar46 from unlock to lock position.

While l prefer to employ the lock mechanism 1% shown in the drawing toeffect rotation of bolt 32, it should be understood, however, that othermeans driven by the cylinder 24 which will provide a component of forcetransverse to cam 33 can be used to convert rotational movement of thecylinder into rotation of bolt 32 around axle 41, and are within thescope of the invention.

To unlock the lock, key 23 is turned in the reverse direction, bolt 32being returned to unlock position by the force of spring 43 uponwithdrawal of bar to from the cam surface 38. In unlock position, boltarm 34 resides flat against base plate 17. Flange itl on arm 34 does notextend outwardly therefrom a distance sufficient to impede freeslidability of door 10 to the right past it.

To install the lock 16 a hole 20 is formed in door panel 12, and thebody 18 of lock mechanism 19 is inserted through it and through the hole21 in base plate 17, and locked in place with nut ZZ. With the cylinder24 turned so that the pins are in the position shown in FIGURE 4, andwith the bolt 32 manually held in lock position, bar 46 is engaged withthe cylinder drive by sliding it through guide 52 above cam surface 38,until the pins 26 and 27 can be properly engaged with the teeth Sti. Nofitting is required on the other door l0.

While I have described the preferred embodiment of my invention, it willbe appreciated that the invention is not limited thereto but includessuch other embodiments as come within the spirit of the claims whichfollow.

What is claimed is:

1. A lock adapted to prevent relative longitudinal movement between apair of sliding doors, said lock comprising, generally planar mountingmeans, an arm mounted by said mounting means for rotation about an axisparallel to the general plane of said mounting means, a cam shaftconnected to said arm and rotatable therewith about said axis, said camshaft presenting a cam surface which lies in a plane approximatelyperpendicular to said arm, a key-operated lock mechanism including agear which is rotated upon operation of said mechanism, said mechanismbeing mounted by said mounting means at a position adjacent said arm,said gear having an axis of rotation which is normal to the generalplane of said mounting means, a bar presenting a series of gear teeth,said teeth being engaged with said gear in rack and pinion relationshiptherewith, said bar being driven linearly in a direction transverse tothe axis of rotation of said gear, guide means presented by saidmounting means for constraining said bar to move in a directiontransverse to the axis of rotation of said arm, said bar engaging saidcam shaft and camming said cam shaft about its axis as said mechanism isoperated, and yieldable spring means urging said arm toward a planegenerally parallel to the plane of said mounting means.

2. A lock for sliding doors, said lock comprising, a base, akey-operated lock mechanism of the type including an element which isrotated about an axis upon operation of said mechanism, said mechanismbeing mounted by said base so that said axis is normal to said base,gear means affixed to said element for rotation therewith about saidaxis, rack means engaged with said gear means for linear movement in adirection transverse to said axis when said mechanism is operated, guidemeans maintaining said rack means in engagement with said gear means andconstraining the movement of said rack means to said linear movement, acam shaft and an arm extending outwardly therefrom, said cam shaft beingmounted by said base for rotation about an axis transverse to the axisof rotation of said element and also transverse to the direction ofmovement of said rack means, said cam shaft presenting a cam surface,said rack presenting a surface adapted to engage said cam surface assaid rack means is moved linearly in response to rotation of saidelement and cause said cam shaft and arm to turn between an unlockposition in which said arm is substantiali parallel to said base and alock position in which said arm extends outwardly from said base, saidsurface of said rack means being parallel to said cam surface when saidarm is in said lock position to positively prevent said arm from beingmoved toward said unlock position, said arm having a flange at its outerend for securing said doors against being sprung apart, and yieldablemeans urging said arm toward said unlock position.

3. A lock for sliding doors comprising,

a base,

a bolt mounted by said base for rotation about an axis parallel to saidbase,

a cam surface connected to said bolt for rotating said bolt about saidaxis in response to lineal camming movement applied to said cam surfacein a direction transverse to said axis,

a key-operated lock mechanism including a member rotated by operation ofsaid mechanism,

a bar moved lineally by rotation of said member,

said bar being aligned with said cam surface so that lineal movement ofsaid bar applies camming movement to said cam surface,

said bar overtravelling said cam surface when said bolt is extendedperpendicularly to said base and thereby deadiocking said bolt inlocking position,

and yieldable means urging said bolt toward said base.

References Cited in the file of this patent UNITED STATES PATENTS2,448,748 Vanderveld Sept. 7, 1948 2,473,285 Koeser .Tune 14, 19492,717,512 Sterling et al. Sept. 13, 1955 2,956,428 Check Oct. 18, 1960

3. A LOCK FOR SLIDING DOORS COMPRISING, A BASE, A BOLT MOUNTED BY SAIDBASE FOR ROTATION ABOUT AN AXIS PARALLEL TO SAID BASE, A CAM SURFACECONNECTED TO SAID BOLT FOR ROTATING SAID BOLT ABOUT SAID AXIS INRESPONSE TO LINEAL CAMMING MOVEMENT APPLIED TO SAID CAM SURFACE IN ADIRECTION TRANSVERSE TO SAID AXIS, A KEY-OPERATED LOCK MECHANISMINCLUDING A MEMBER ROTATED BY OPERATION OF SAID MECHANISM, A BAR MOVEDLINEALLY BY ROTATION OF SAID MEMBER, SAID BAR BEING ALIGNED WITH SAIDCAM SURFACE SO THAT LINEAL MOVEMENT OF SAID BAR APPLIES CAMMING MOVEMENTTO SAID CAM SURFACE, SAID BAR OVERTRAVELLING SAID CAM SURFACE WHEN SAIDBOLT IS EXTENDED PERPENDICULARLY TO SAID BASE AND THEREBY DEADLOCKINGSAID BOLT IN LOCKING POSITION, AND YIELDABLE MEANS URGING SAID BOLTTOWARD SAID BASE.